ioperm() with ports above 0x3ff

Samuel Thibault
Fri Feb 22 11:08:00 GMT 2008

Daniel Noll, le Fri 22 Feb 2008 08:50:37 +1100, a écrit :
> On Friday 22 February 2008 07:46:18 Samuel Thibault wrote:
> > Yes: on Linux ioperm doesn't work above 0x400.  On Linux, so as to
> > access ports above 0x400 you need to use iopl(), that's why ioperm in
> > cygwin does this.  Now, allowing >= 0x400 would be possible in cygwin's
> > ioperm, but then you'd get problems when using the code on Linux...  The
> > truly proper way is really to use iopl().
> On the other hand the iopl() man page specifically says that it shouldn't be 
> used in processes intended to be portable. ;-D

To non-Linux environments, yes, but Cygwin is meant to be

Anyway, tinkering with ports is definitely not portable ;)


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